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<h1 class="title">screenshot.cpp 示例文件</h1>
<span class="subtitle">desktop/screenshot/screenshot.cpp</span>
<!-- $$$desktop/screenshot/screenshot.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
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  ** BSD License Usage
  ** Alternatively, you may use this file under the terms of the BSD license
  ** as follows:
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  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
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  ** $QT_END_LICENSE$
  **
  ****************************************************************************/</span>

  <span class="preprocessor">#include &lt;QtWidgets&gt;</span>

  <span class="preprocessor">#include &quot;screenshot.h&quot;</span>

  Screenshot<span class="operator">::</span>Screenshot()
      :  screenshotLabel(<span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(<span class="keyword">this</span>))
  {
      screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>setSizePolicy(<span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>Expanding<span class="operator">,</span> <span class="type"><a href="qsizepolicy.html">QSizePolicy</a></span><span class="operator">::</span>Expanding);
      screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>setAlignment(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>AlignCenter);

      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> screenGeometry <span class="operator">=</span> <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>desktop()<span class="operator">-</span><span class="operator">&gt;</span>screenGeometry(<span class="keyword">this</span>);
      screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>setMinimumSize(screenGeometry<span class="operator">.</span>width() <span class="operator">/</span> <span class="number">8</span><span class="operator">,</span> screenGeometry<span class="operator">.</span>height() <span class="operator">/</span> <span class="number">8</span>);

      <span class="type"><a href="qvboxlayout.html">QVBoxLayout</a></span> <span class="operator">*</span>mainLayout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qvboxlayout.html">QVBoxLayout</a></span>(<span class="keyword">this</span>);
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(screenshotLabel);

      <span class="type"><a href="qgroupbox.html">QGroupBox</a></span> <span class="operator">*</span>optionsGroupBox <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgroupbox.html">QGroupBox</a></span>(tr(<span class="string">&quot;Options&quot;</span>)<span class="operator">,</span> <span class="keyword">this</span>);
      delaySpinBox <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qspinbox.html">QSpinBox</a></span>(optionsGroupBox);
      delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>setSuffix(tr(<span class="string">&quot; s&quot;</span>));
      delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>setMaximum(<span class="number">60</span>);

      connect(delaySpinBox<span class="operator">,</span> <span class="type">QOverload</span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">&gt;</span><span class="operator">::</span>of(<span class="operator">&amp;</span><span class="type"><a href="qspinbox.html">QSpinBox</a></span><span class="operator">::</span>valueChanged)<span class="operator">,</span>
              <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&amp;</span>Screenshot<span class="operator">::</span>updateCheckBox);

      hideThisWindowCheckBox <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qcheckbox.html">QCheckBox</a></span>(tr(<span class="string">&quot;Hide This Window&quot;</span>)<span class="operator">,</span> optionsGroupBox);

      <span class="type"><a href="qgridlayout.html">QGridLayout</a></span> <span class="operator">*</span>optionsGroupBoxLayout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgridlayout.html">QGridLayout</a></span>(optionsGroupBox);
      optionsGroupBoxLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(<span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(tr(<span class="string">&quot;Screenshot Delay:&quot;</span>)<span class="operator">,</span> <span class="keyword">this</span>)<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">0</span>);
      optionsGroupBoxLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(delaySpinBox<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span>);
      optionsGroupBoxLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(hideThisWindowCheckBox<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">2</span>);

      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(optionsGroupBox);

      <span class="type"><a href="qhboxlayout.html">QHBoxLayout</a></span> <span class="operator">*</span>buttonsLayout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qhboxlayout.html">QHBoxLayout</a></span>;
      newScreenshotButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">&quot;New Screenshot&quot;</span>)<span class="operator">,</span> <span class="keyword">this</span>);
      connect(newScreenshotButton<span class="operator">,</span> <span class="operator">&amp;</span><span class="type"><a href="qpushbutton.html">QPushButton</a></span><span class="operator">::</span>clicked<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&amp;</span>Screenshot<span class="operator">::</span>newScreenshot);
      buttonsLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(newScreenshotButton);
      <span class="type"><a href="qpushbutton.html">QPushButton</a></span> <span class="operator">*</span>saveScreenshotButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">&quot;Save Screenshot&quot;</span>)<span class="operator">,</span> <span class="keyword">this</span>);
      connect(saveScreenshotButton<span class="operator">,</span> <span class="operator">&amp;</span><span class="type"><a href="qpushbutton.html">QPushButton</a></span><span class="operator">::</span>clicked<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&amp;</span>Screenshot<span class="operator">::</span>saveScreenshot);
      buttonsLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(saveScreenshotButton);
      <span class="type"><a href="qpushbutton.html">QPushButton</a></span> <span class="operator">*</span>quitScreenshotButton <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">&quot;Quit&quot;</span>)<span class="operator">,</span> <span class="keyword">this</span>);
      quitScreenshotButton<span class="operator">-</span><span class="operator">&gt;</span>setShortcut(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>CTRL <span class="operator">+</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Q);
      connect(quitScreenshotButton<span class="operator">,</span> <span class="operator">&amp;</span><span class="type"><a href="qpushbutton.html">QPushButton</a></span><span class="operator">::</span>clicked<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&amp;</span><span class="type"><a href="qwidget.html">QWidget</a></span><span class="operator">::</span>close);
      buttonsLayout<span class="operator">-</span><span class="operator">&gt;</span>addWidget(quitScreenshotButton);
      buttonsLayout<span class="operator">-</span><span class="operator">&gt;</span>addStretch();
      mainLayout<span class="operator">-</span><span class="operator">&gt;</span>addLayout(buttonsLayout);

      shootScreen();
      delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>setValue(<span class="number">5</span>);

      setWindowTitle(tr(<span class="string">&quot;Screenshot&quot;</span>));
      resize(<span class="number">300</span><span class="operator">,</span> <span class="number">200</span>);
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>resizeEvent(<span class="type"><a href="../qtgui/qresizeevent.html">QResizeEvent</a></span> <span class="operator">*</span> <span class="comment">/* event */</span>)
  {
      <span class="type"><a href="../qtcore/qsize.html">QSize</a></span> scaledSize <span class="operator">=</span> originalPixmap<span class="operator">.</span>size();
      scaledSize<span class="operator">.</span>scale(screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>size()<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>KeepAspectRatio);
      <span class="keyword">if</span> (<span class="operator">!</span>screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>pixmap() <span class="operator">|</span><span class="operator">|</span> scaledSize <span class="operator">!</span><span class="operator">=</span> screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>pixmap()<span class="operator">-</span><span class="operator">&gt;</span>size())
          updateScreenshotLabel();
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>newScreenshot()
  {
      <span class="keyword">if</span> (hideThisWindowCheckBox<span class="operator">-</span><span class="operator">&gt;</span>isChecked())
          hide();
      newScreenshotButton<span class="operator">-</span><span class="operator">&gt;</span>setDisabled(<span class="keyword">true</span>);

      <span class="type"><a href="../qtcore/qtimer.html">QTimer</a></span><span class="operator">::</span>singleShot(delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>value() <span class="operator">*</span> <span class="number">1000</span><span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&amp;</span>Screenshot<span class="operator">::</span>shootScreen);
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>saveScreenshot()
  {
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> format <span class="operator">=</span> <span class="string">&quot;png&quot;</span>;
      <span class="type"><a href="../qtcore/qstring.html">QString</a></span> initialPath <span class="operator">=</span> <span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>writableLocation(<span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>PicturesLocation);
      <span class="keyword">if</span> (initialPath<span class="operator">.</span>isEmpty())
          initialPath <span class="operator">=</span> <span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>currentPath();
      initialPath <span class="operator">+</span><span class="operator">=</span> tr(<span class="string">&quot;/untitled.&quot;</span>) <span class="operator">+</span> format;

      <span class="type"><a href="qfiledialog.html">QFileDialog</a></span> fileDialog(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">&quot;Save As&quot;</span>)<span class="operator">,</span> initialPath);
      fileDialog<span class="operator">.</span>setAcceptMode(<span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>AcceptSave);
      fileDialog<span class="operator">.</span>setFileMode(<span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>AnyFile);
      fileDialog<span class="operator">.</span>setDirectory(initialPath);
      <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> mimeTypes;
      foreach (<span class="keyword">const</span> <span class="type"><a href="../qtcore/qbytearray.html">QByteArray</a></span> <span class="operator">&amp;</span>bf<span class="operator">,</span> <span class="type"><a href="../qtgui/qimagewriter.html">QImageWriter</a></span><span class="operator">::</span>supportedMimeTypes())
          mimeTypes<span class="operator">.</span>append(QLatin1String(bf));
      fileDialog<span class="operator">.</span>setMimeTypeFilters(mimeTypes);
      fileDialog<span class="operator">.</span>selectMimeTypeFilter(<span class="string">&quot;image/&quot;</span> <span class="operator">+</span> format);
      fileDialog<span class="operator">.</span>setDefaultSuffix(format);
      <span class="keyword">if</span> (fileDialog<span class="operator">.</span>exec() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="qdialog.html">QDialog</a></span><span class="operator">::</span>Accepted)
          <span class="keyword">return</span>;
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> fileName <span class="operator">=</span> fileDialog<span class="operator">.</span>selectedFiles()<span class="operator">.</span>first();
      <span class="keyword">if</span> (<span class="operator">!</span>originalPixmap<span class="operator">.</span>save(fileName)) {
          <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>warning(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">&quot;Save Error&quot;</span>)<span class="operator">,</span> tr(<span class="string">&quot;The image could not be saved to \&quot;%1\&quot;.&quot;</span>)
                               <span class="operator">.</span>arg(<span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(fileName)));
      }
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>shootScreen()
  {
      <span class="type"><a href="../qtgui/qscreen.html">QScreen</a></span> <span class="operator">*</span>screen <span class="operator">=</span> <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>primaryScreen();
      <span class="keyword">if</span> (<span class="keyword">const</span> <span class="type"><a href="../qtgui/qwindow.html">QWindow</a></span> <span class="operator">*</span>window <span class="operator">=</span> windowHandle())
          screen <span class="operator">=</span> window<span class="operator">-</span><span class="operator">&gt;</span>screen();
      <span class="keyword">if</span> (<span class="operator">!</span>screen)
          <span class="keyword">return</span>;

      <span class="keyword">if</span> (delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>value() <span class="operator">!</span><span class="operator">=</span> <span class="number">0</span>)
          <span class="type"><a href="qapplication.html">QApplication</a></span><span class="operator">::</span>beep();

      originalPixmap <span class="operator">=</span> screen<span class="operator">-</span><span class="operator">&gt;</span>grabWindow(<span class="number">0</span>);
      updateScreenshotLabel();

      newScreenshotButton<span class="operator">-</span><span class="operator">&gt;</span>setDisabled(<span class="keyword">false</span>);
      <span class="keyword">if</span> (hideThisWindowCheckBox<span class="operator">-</span><span class="operator">&gt;</span>isChecked())
          show();
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>updateCheckBox()
  {
      <span class="keyword">if</span> (delaySpinBox<span class="operator">-</span><span class="operator">&gt;</span>value() <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) {
          hideThisWindowCheckBox<span class="operator">-</span><span class="operator">&gt;</span>setDisabled(<span class="keyword">true</span>);
          hideThisWindowCheckBox<span class="operator">-</span><span class="operator">&gt;</span>setChecked(<span class="keyword">false</span>);
      } <span class="keyword">else</span> {
          hideThisWindowCheckBox<span class="operator">-</span><span class="operator">&gt;</span>setDisabled(<span class="keyword">false</span>);
      }
  }

  <span class="type">void</span> Screenshot<span class="operator">::</span>updateScreenshotLabel()
  {
      screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>setPixmap(originalPixmap<span class="operator">.</span>scaled(screenshotLabel<span class="operator">-</span><span class="operator">&gt;</span>size()<span class="operator">,</span>
                                                       <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>KeepAspectRatio<span class="operator">,</span>
                                                       <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>SmoothTransformation));
  }

</pre>
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<!-- @@@desktop/screenshot/screenshot.cpp -->
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